Rios failed drug test after Pacquiao fight

Former lightweight titlist Brandon Rios, who agreed to random drug testing by the Voluntary Anti-Doping Association for his November 23 welterweight showdown with Manny Pacquiao in Macau, failed his post-fight drug test.

Rios, who lost a shutout decision in a non-competitive fight with Pacquiao, tested positive for the banned stimulant methylhexaneamine, often used as a dietary supplement but also a performance-enhancing drug.

Rios was notified shortly after the fight, and, according to Top Rank promoter Bob Arum, he already has been suspended by the Macau commission that regulated the fight. Arum said he thought the suspension was for five or six months but was unsure.

"I can say unequivocally that it was not a steroid-related substance," Arum told ESPN.com. "It was some substance that was like a minor kind of thing that you're not supposed to take, something you take for weight loss, like a diuretic. They say it's not a steroid but it was something you should not have in your urine after a fight. So it went to the [Macau] commission that was in charge of the fight, and they gave him a suspension. He is allowed to appeal."

The Macau commission was set up by the WBO to oversee the fight, since China does not have a commission that oversees professional boxing. The WBO sanctioned the fight for one of its regional titles.

"Brandon had the genius, Ariza, trying to help him make weight," Arum said. "It is not the fighter's fault. It's the people who are conditioning him. He's following orders on what to eat and drink, so I don't blame him. Brandon's not a nutritionist. It's generally the conditioner's fault if the kid doesn't make weight. This is Ariza's fault.

"The fighter, in my experience, follows religiously what he is told to eat and drink. If he's being advised by people who consider themselves experts, but who really don't know s***, that's when you get in trouble."

Ariza is in San Antonio, working as Marcos Maidana's strength and conditioning coach for his welterweight title challenge against Adrien Broner on Saturday night at the Alamodome. After the weigh-in Friday, Ariza briefly addressed Rios' positive test.

"We disclosed everything we were taking," Ariza told ESPN.com.

When asked whether he was surprised that Rios tested positive, he declined to answer. Robert Garcia, who trains Rios and Maidana, also is in San Antonio and said he had spoken to Rios about the positive test but didn't want to get into details.

"It was something [in his urine test], but I don't know what it is," Garcia said. "I am focused on 'Chino' [Maidana]. I know Brandon was testing and it was the one after the fight [that he failed]. We have to look into it. We don't want to have a bad name or a bad reputation. But right now I am focusing on Maidana."

Rios had passed his previous tests before the final one administered after the fight. Pacquiao successfully completed the VADA program.

"VADA follows its written results management policy and reports all results in writing to the athlete, promoter, [Association of Boxing Commissions] and the relevant commissions, who can confirm individual results," Goodman said.

"VADA also publicly reports when an athlete has successfully completed the program. VADA's role is to administer high-quality testing. It is not our role to determine whether or not disciplinary action is appropriate."

VADA is the same organization that caught Lamont Peterson and Andre Berto with banned substances in random tests leading up to their rematches with Amir Khan and Victor Ortiz, respectively, forcing the high-profile world title fights to be canceled.